<template>
  <div class="todo-footer" v-show="total > 0">
    <label>
      <input type="checkbox" @change="handleCheckAll"
             :checked="totalDone === total && total > 0"/>
    </label>
    <span>
          <span>已完成{{ totalDone }}</span> / 全部{{ total }}
        </span>
    <button class="btn btn-danger" @click="$emit('clear-all-todo')">清除已完成任务</button>
  </div>
</template>
<script>
export default {
  name: 'MyFooter',
  props: ['todos',
    // 'clearAllTodo', 'checkAllTodo'
  ],
  data() {
    return {
    }
  },
  computed: {
    totalDone() {
      return this.todos
          .reduce((pre, cur) =>
                  pre + (cur.done ? 1 : 0)
              , 0)
    },
    total() {
      return this.todos.length
    }
  },
  methods: {
    handleCheckAll(e) {
      // this.checkAllTodo(e.target.checked)
      this.$emit('check-all-todo', e.target.checked)
    }
  }
}
</script>


<style scoped lang="css">
/*footer*/
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}

</style>